i have a 84 camaro. it has air conditioning on it, when i turn the air the pump motor will turn on for a fewe seconds then it will turn off. it wont stay on long enough to push enough cold air through the car. i was told it might be a relay of some sort. but i have no idea where it is or what im lookin for. any help would be appreciated.
thanks

 

YOUR out of Freon, it's protecting itself. Go have your system checked for leaks and refilled. When it senses that it can't build pressure it turns off the compressor so not to seze it do to not having Freon lubercation.

 

if it didnt have any freon would it stil lget cold? cuz it blows cold air.

 

Have your freon level checked, you could just be low, NO it's not a relay if the compressor cuts in.

 

If you thinking it's suppose to run constant it's not, it is suppose to cycle based on low pressure side sensor reading.

 

hmmmm guess ill have to get it checked.

 

when i turned my a/c on the compressor cycled every few seconds, so i needed to fill up with some r-12, the system took about one full can, and the cycling stopped and my dual electric fans came on, and of course the air was freezin cold...

once the fans came one i knew it was at least at the min. pressure for the a/c pressure switch to activate..

 

The key there is "few secs" you will see a pattern, it will keep checking, other wise you won't be able to suck in new freon.

 

Actually your AC isnt suppose to cycle on and off. When i got my 91 it was bone flat on R12. I had a jug of it on loan from a friend. It took a lil over 2 lbs, had a 36-38 psi suction pressure and blows out 39-40* air in heat wave. And the compressor dose not cycle. the cycle is a saftey only, for the compressor. It by no means is used as a pressure control. Lack of freon, means lack of oil flow, so when pressure goes to low the low press switch opens till pressure equalizes again. Then it closes, then it opens (noticing a pattern?). This will continue till freon is added to the point where the switch stays open. I think that the factory setting is around 25 psi. If you have any questions, or comments just pm me and ill listen and answer.

 

BTW if you have a full charge and the compressor is running but the air isnt that cold, your compressor may be failing. a new compressor increases capacity a lot.

 

91TPI5.7 what you say there is correct except on cooler days, the compressor will cycle so that it doesn't "freeze up", this is checked by the sensor on the high pressure side, I don't have my factory manual sitting in front of me but would be up in the 300psi range I believe, might be lower, can't remember.

Just because your car isn't blowing cool air and the system is full of freon doesn't mean your compressor has bit the dust, sometimes it can be a problem with the expansion orifice like pluged up with metal from the current compressor or former ones, also a collapsed orifice, or a broken orifice that is not alowing the compressor to build any pressure, just letting the freon move thru the system. I've seen them all.

Your advice of getting a new compressor is good because if your buying R-12 don't want to waste doing it again. Also I might add that GETTING A NEW compressor instead of that rebuilt crap is a VERY good idea. Only 100 dollars different at Autozone but will be a lot stronger and last twice as long if not longer.